The recent horrific factory collapse in Dhaka, Bangladesh drew renewed attention to the link between global garment industry brands and the working conditions of garment factory employees at the far end of the supply chain.

School of Data, an effort by the Open Knowledge Foundation to provide training to journalists, advocates, and the general public on modern data analysis techniques, used the interest generated by the tragedy to organize a data training event around the issue of global garment supply chains. Teams around the world focused on a range of issues including recommended standards for the release of factory information to visualizations of retailers global connectivity and revenue.

In New York, a team lead by Alyssa Wright and Andrew Salzberg gathered to understand the role that OpenStreetMap might play in the effort to better understand global supply chains. The New York City team was composed of representatives from related projects, including Open Cities Project and Sourcemap. Together they offered introductory training to other international School of Data teams on how OpenStreetMap can be used as a tool for data collection, sharing, and analysis.

After a hands-on tutorial on editing building footprints in JOSM the Bangladesh team noticed that a large number of factories in the database were located in the Chittagong Export Processing Zone in Chittagong. To help understand the physical fabric of this zone, the NYC team focused their efforts on mapping the complete set of building footprints for the area, below.